As illustrated in FIG. 1, human mouth includes an upper jaw bone or maxilla 140 and a lower jaw bone or mandible 142, both operationally linked to perform chewing function. A set of upper teeth 141, and a set of lower teeth 143 are located on the respective jaw bones. Generally, as shown in FIG. 1, maxilla 140 is protracted a certain distance (A) anteriorly with respect to mandible 142. A malocclusion where mandible 145 is positioned posteriorly with respect to maxilla 144 a certain distance (X) as illustrated in FIG. 2 is classified as Class II malocclusion. On the other hand, a malocclusion where mandible 147 is positioned anteriorly with respect to maxilla 146 a certain distance (Y) as illustrated in FIG. 3 is classified as Class III malocclusion.
Positioning devices between upper and lower jaws are commonly used in orthodontics to treat patients with Class II malocclusions. Examples of such devices are shown in FIGS. 4 to 6. Common feature of these devices is that they are composed of two separate assemblies. Each assembly is attached to one of either maxillary or mandibular jaws. When the jaws are open, two assemblies are separated from each other. They come in contact when the jaws are closed, and a forward moving force is applied to the mandibular jaw to reposition it relative to the maxillary jaw.
Existing, positioning devices for intraoral applications, in general, has obstruction elements which contact when the jaws are proximate to each other in their uncorrected orientation, and prevent jaws from being fully closed. To close the jaws completely, mandibular jaw is pushed to its corrected position to clear the obstruction surface, and only then, jaws can be fully closed. This requires a controlled action by the patient, and it can be annoying especially in early stages of the treatment. A fluid motion that forces the mandibular jaw to its correct position as the jaws are being closed would receive better acceptance by the patients.